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<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>

<body>
<script>
    // forEach 迭代(遍历) 数组
    const arr = [1, 2, 3];
    let sum = 0;
    arr.forEach(function (value, index, array) {
        console.log('每个数组元素' + value);
        console.log('每个数组元素的索引号' + index);
        console.log('数组本身' + array);
        sum += value;
    })
    console.log(sum);
</script>
</body>

</html>
